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arXiv · 1209.4361

An attempt at a resonating mean-field theoretical description of thermal behavior of two-gap superconductivity

Seiya Nishiyama·Joao da Providencia·Constanca Providencia·Hiromasa Ohnishi
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Abstract

The resonating mean-field theory (Res-MFT) has been applied and shown to effectively describe two-gap superconductivity (SC). Particularly at T=0 using a suitable chemical potential, the two-gap SC in MgB2 has been well described by the Res-Hartree-Bogoliubov theory (Res-HBT). The Res-HB ground state generated with HB wave functions almost exhausts the ground-state correlation energy in all the correlation regimes. In this paper we make an attempt at a Res-MF theoretical description of thermal behavior of the two-gap SC. In an energy-gap case we find a new formula leading to a higher Tc than the Tc of the usual HB formula.

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Seiya Nishiyama, Joao da Providencia, Constanca Providencia, Hiromasa Ohnishi. 2012-09-18. An attempt at a resonating mean-field theoretical description of thermal behavior of two-gap superconductivity. https://doi.org/10.1142/s0217979213500793

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